Preservation of biological samples, especially clinical samples, is necessary in order to ensure continued use of the sample for various levels of analysis. Oftentimes, an investigator or physician will want to run multiple tests on a single sample so that results in one test may be correlated with the others. Moreover, where clinical samples are difficult, uncomfortable, or painful to obtain, it is preferred to not have to do so on multiple occasions for the same subject or patient. As such, a need exists to minimize the amount of sample used in certain tests so as to maximize the number of tests that may be performed on a single sample.
As just one example, cervical samples are commonly collected during gynecological examinations. Where abnormal cytological examinations of such samples are observed, it is often beneficial to determine whether the tissue is infected with a human papillomavirus (HPV) associated with cervical cancer. The most commonly used tests for HPV infection typically only distinguish between high-risk and low-risk HPV infections, but cannot distinguish between various species of high-risk or low-risk HPVs. In some circumstance, it may be useful to determine the specific genotype of HPV infection.
The digene HPV Genotyping PS™ Test (PS test) was developed for the specific detection of HPV 16, 18, and 45 and is intended to be utilized as a reflex genotyping test for samples qualitatively determined to contain a high-risk human papillomavirus (HR-HPV). The PS™ test often is used to genotype HR-HPV-positive samples identified by the digene HC2™ HPV test (HC2™ test), which is described in U.S. Pat. Nos. 4,849,331; 4,849,332; 4,849,334; 4,908,306; 5,411,857; 5,643,715; 5,712,092; 5,876,922; 5,952,487; 5,958,674; 6,107,086; and 5,981,173, each of which is herein incorporated by reference. Both the PS™ test and the HC2™ test are based on hybrid capture technology, which is described in, among other references, U.S. Pat. Nos. 4,732,847; 4,865,980; and 6,228,578 B1, each of which is herein incorporated by reference. The PS™ test has been demonstrated to be compatible with SPECIMEN TRANSPORT MEDIUM™ (STM) media and the commonly used liquid based cytology (LBC) media, PRESERVCYT® (PC). However, it has not been tested with another frequently used LBC media, SUREPATH®. In addition, the intended use of the PS™ Test is to detect HPV genotypes separately, which requires separate aliquots of each patient specimen for each genotype tested. In addition, some specimens may lack sufficient volume after qualitative testing for performing separate tests for each genotype to be evaluated. Accordingly, it would be beneficial to develop materials and methods for performing the PS™ test in SP samples and with reduced volume.